The estimation of aboveground biomass and nutrient pools of understorey plants in closed Norway spruce forests and on clearcuts

The estimation model PhytoCalc allows a non-destructive quantification of dry weight and nutrient pools of understorey plants in forests by using the relationship between species biomass, cover and mean shoot length. The model has been validated with independent samples in several German forest types and can be a useful tool in forest monitoring. However, in open areas within forests (e.g. clearcuts), the current model version underestimates biomass and produces unreliable nutrient pool estimations. Thus, tissue density, as approximated by leaf dry matter content (LDMC), is systematically higher under high light compared to low light conditions. We demonstrate that the ratio of LDMC under clearcut conditions to LDMC under forest conditions can be used to adjust the PhytoCalc model to clearcut conditions. We investigated the LDMC ratio of five exemplary species commonly occurring on clearcuts. Integrating the square of the ratio as a correction factor improved estimates of biomass to more than 70% fit between observations and predictions. Results also suggest this ratio can be used to correct nutrient concentrations modelled in PhytoCalc, which tend to be overestimated in clearcuts. As morphological groups of plant species exhibit significantly different ratios, we advise using group-specific correction factors for clearcut adjustments in the future

Chironomiden als Anzeiger für die holozäne Klima- und Umweltgeschichte von Store Koldewey in Nordost-Grönland

Sedimentkerne aus zwei hocharktischen Seen (Duck und Hjort Lake) auf Store Koldewey, einer Insel auf Nordostgrönland, wurden auf ihre fossilen Chironomiden-Vergesellschaftungen untersucht. Im gesamten Holozän konnten 18 Chironomiden-Arten im Duck Lake und 21 im Hjort Lake identifiziert werden. Erste Chironomiden erscheinen im Hjort Lake bei ca. 9500 Kalenderjahre BP und ca. 500 Jahre später im Duck Lake. Für diese Periode wird in Ostgrönland eine signifikante Erwärmung angenommen. Jedoch bleiben die Abundanz und die Diversität der Chironomiden im Laufe des Frühholozäns in beiden Seen gering. Eine mögliche Ursache könnte der Einfluss der kalten, Meereis führenden Ostgrönlandströmung sein, welche vom Arktischen Ozean in Richtung Süden an Ostgrönland entlang verläuft. Der Beginn des Mittelholozäns wird durch eine steigende Abundanz von Chironomiden im Hjort Lake ab ca. 8000 Kalenderjahren BP und im Duck Lake ab ca. 6800 Kalenderjahren BP angezeigt. Die Chironomiden-Vergesellschaftung im Mittelholozän ähnelt derer von heutzutage leicht wärmeren Seen. Die zeitliche Verschiebung der Chironomiden-Vergesellschaftungen zwischen beiden Seen ist vermutlich auf Nährstoffschwankungen zurückzuführen. Eine wahrscheinlich höhere Schmelzwasserzufuhr in den Hjort Lake, aufgrund eines größeren Einzugsgebietes, führte diesem See möglicherweise mehr Nährstoffe als dem Duck Lake zu, wodurch sich die Chironomiden-Vergesellschaftungen im Hjort Lake vermutlich früher entfalten konnten. Das Verschwinden von Chironomiden mit Tendenz zu wärmeren Bedingungen erfolgt zeitgleich zu einem Kältetrend bei ca. 5000 Kalenderjahre BP in Nordostgrönland. Ein statistischer Vergleich mit Chironomiden und Umweltparametern von Seen der kanadischen Arktis (Gajewski et al., 2005), Oberflächendaten von Chironomiden aus weiteren Seen auf Store Koldewey und Geographical Society Ø sowie die im Holozän vorkommenden Chironomiden aus Duck und Hjort Lake, deuten den Beginn kälterer Temperaturen an. Temperatur scheint für die Häufigkeit und die Zusammensetzung der Chironomiden in den Seen auf Store Koldewey der steuernder Faktor zu sein. Die Untersuchung der Chironomiden aus Store Koldewey zählt zu den ersten von Nordostgrönland. Sie hat gezeigt, dass sich Chironomiden als Klima-Proxy für diese hocharktische Region eignen

Individualized Template MRI Is a Valid and Reliable Alternative to Individual MRI for Spatial Tracking in Navigated TMS Studies in Healthy Subjects

Objectives: Navigated transcranial magnetic stimulation (nTMS) provides significant benefits over classic TMS. Yet, the acquisition of individual structural magnetic resonance images (MRIindividual) is a time-consuming, expensive, and not feasible prerequisite in all subjects for spatial tracking and anatomical guidance in nTMS studies. We hypothesize that spatial transformation can be used to adjust MRI templates to individual head shapes (MRIwarped) and that TMS parameters do not differ between nTMS using MRIindividual or MRIwarped. Materials and Methods: Twenty identical TMS sessions, each including four different navigation conditions, were conducted in 10 healthy subjects (one female, 27.4 ± 3.8 years), i.e., twice per subject by two researchers to additionally assess interrater reliabilities. MRIindividual were acquired for all subjects. MRIwarped were obtained through the spatial transformation of a template MRI following a 5-, 9-and 36-point head surface registration (MRIwarped_5, MRIwarped_9, MRIwarped_36). Stimulation hotspot locations, resting motor threshold (RMT), 500 μV motor threshold (500 μV-MT), and mean absolute motor evoked potential difference (MAD) of primary motor cortex (M1) examinations were compared between nTMS using either MRIwarped variants or MRIindividual and non-navigated TMS. Results: M1 hotspots were spatially consistent between MRIindividual and MRIwarped_36 (insignificant deviation by 4.79 ± 2.62 mm). MEP thresholds and variance were also equivalent between MRIindividual and MRIwarped_36 with mean differences of RMT by -0.05 ± 2.28% maximum stimulator output (%MSO; t (19) = -0.09, p = 0.923), 500 μV-MT by -0.15 ± 1.63%MSO (t (19) = -0.41, p = 0.686) and MAD by 70.5 ± 214.38 μV (t (19) = 1.47, p = 0.158). Intraclass correlations (ICC) of motor thresholds were between 0.88 and 0.97. Conclusions: NTMS examinations of M1 yield equivalent topographical and functional results using MRIindividual and MRIwarped if a sufficient number of registration points are used

Metal uptake and distribution in the zebrafish (Danio rerio) embryo: differences between nanoparticles and metal ions

Quantitative data on nanoparticle and cation uptake are compared in a compartment-specific way and distinct differences between metals were identified

Non-native vascular plant species in strict forest nature reserves in Rhineland-Palatinate

Floristische und vegetationskundliche Daten aus 21 Naturwaldreservaten (NWR) in Rheinland-Pfalz wurden hinsichtlich ihres Anteils an gebietsfremden Gefäßpflanzenarten (Neophyten i. w. S.) ausgewertet und überregional verglichen, um generelle Trends in der Naturnähe und der natürlichen Waldentwicklung - unabhängig von lokal wirkenden Faktoren – aufzuzeigen. Neben überwiegend zonalen, naturnahen Buchenwäldern bodensaurer Standorte umfasst der Datensatz auch drei Auenwald-Standorte und zwei Moorbirken-Bruchwälder. Als Besonderheit im Ver-gleich zu anderen Bundesländern hat Rheinland-Pfalz zwei NWR mit hohen Douglasien-Anteilen ausgewiesen, um deren Entwicklung ohne forstliche Nutzung zu dokumentieren. Von diesen beiden NWR und zwei NWR mit besonderer Dynamik nach Windwurf sowie einem weitgehend ungestörtem NWR im Biosphärenreservat Pfälzer Wald liegen auch Wiederholungsinventuren vor, die erste Hinweise auf die langfristige Entwicklung des Neophyten-Anteils in NWR liefern. Durch einen Vergleich gezäunter und ungezäunter Flächen in NWR konnte der Schalenwildein-fluss, durch den Vergleich mit angrenzenden, weiterhin bewirtschafteten Beständen der Einfluss der forstlichen Nutzung auf den Anteil gebietsfremder Arten an der Vegetation analysiert wer-den. Gebietsfremde Arten spielen in den naturnahen, nicht mehr bewirtschafteten NWR in Rhein-land-Pfalz insgesamt eine untergeordnete Rolle. Vor allem krautige Neophyten sind ausgespro-chen gering vertreten, insbesondere in den naturnahen Buchenwald-NWR. Auch von Impatiens glandulifera, die in allen Auen-NWR am Rhein vorkommt, geht bisher weder ein Verdrängen ein-heimischer Arten noch ein Verlust an Diversität und Naturnähe aus. Den größten Anteil unter den gebietsfremden Arten bilden die nicht-autochthonen Gehölze, die in der Vergangenheit 142 forstlich angebaut wurden und von denen sich vor allem Picea abies, Larix decidua und Pseudotsuga menziesii in den NWR vielfach spontan verjüngen. Wiederholungsinventuren zeigen unterschied-liche Entwicklungen im Anteil gebietsfremder Arten, wobei vorangegangene Störungen (z. B. Windwurf) einen wesentlichen Einfluss ausüben. Im Vergleich der Aufnahmen von zwei Dougla-sien-reichen NWR kam es innerhalb eines Jahrzehnts zu einem starken Rückgang der Douglasie. Sie ist dort vor allem in der Konkurrenz zur Buche unterlegen, so dass sich ohne waldbauliche Unterstützung hier der Naturnähegrad wieder erhöht hat. Ohne Schalenwildeinfluss (hauptsäch-lich Reh- und Rotwild) sind gebietsfremde Arten tendenziell erfolgreicher. Insbesondere Picea abies und Pseudotsuga menziesii waren im Zaun in Strauchschichthöhe stärker vertreten als außer-halb. Im Vergleich mit bewirtschafteten Wäldern ist der Anteil gebietsfremder Arten in unbewirt-schafteten NWR absolut gesehen niedriger. Durch den geringen Artenreichtum an Gefäß-pflanzen und einem geringeren Deckungsgrad der Bodenvegetation im NWR gleichen sich die Unterschiede zwischen (naturnah) bewirtschafteten und nicht bewirtschafteten Wäldern jedoch weitgehend aus.Floristic data and data from vegetation surveys were compared across 21 strict forest nature reserves (SFNR) in Rhineland-Palatinate (south-west Germany) concerning the proportion of non-native plant species (alien plant species or neophytes) in order to detect general trends in the naturalness and dynamics of unmanaged forests in Central Europe. Beside the predominant zonal and close-to-nature oligotrophic beech forests the data set included three eutrophic floodplain forests and two oligotrophic bog woodlands. Apart from other German federal states Rhineland-Palatinate established two SFNR with a high proportion of the alien species Douglas fir in order to study the further development of these stands without forest management. Resurveys of these two SFNR and two further SFNR with a high dynamic after windthrow as well as an undisturbed SFNR in the biosphere reserve Palatinate Forest give the opportunity to analyze long-term trends of alien species. A comparison of fenced and unfenced plots allowed an assessment of browsing effects, a comparison of SFNR with close-by managed forests an assessment of forest manage-ment impacts on the relevance of neophytes in forest vegetation. In a regional context the proportion of non-indigenous plant species in unmanaged SFNR in Rhineland-Palatinate is low. Especially in close-to-nature beech forest SFNR alien herb layer species are rare. Even Impatiens glandulifera – well established in all of the investigated floodplain SFNR of the Rhine valley – seems not to suppress native plant species and shows no negative impact on diversity and the degree of naturalness of the riparian forests. Phanerophytes (woody species) have the highest proportion among aliens in the dataset, mainly introduced by planting in the past. Among them especially Picea abies, Larix decidua, and Pseudotsuga menziesii showed the ability to regenerate naturally in the SFNR. Resurveys of disturbed and undisturbed SFNR indi-cated a divergent development in the proportion of alien species. SFNR stands with Douglas fir Wolfgang Schmidt, Michaela Dölle, Steffi Heinrichs & Patricia Balcar: Gebietsfremde Gefäßpflanzen in Naturwaldreservaten von Rheinland-Pfalz 143 showed a strong decrease of Pseudotsuga menziesii mainly outcompeted by beech within one dec-ade. Therefore, without forest management naturalness of the stands has increased. Without deer browsing (mainly roe and red deer) alien plant species seemed to be more successful. Especially Picea abies and Pseudotsuga menziesii are limited by browsing as fencing increased species frequency and abundance of these woody species within the shrub layer. In general, forest management increased the total number of neophytes. But due to the decreasing species richness and the lower coverage of understorey vegetation in the unmanaged SFNR the differences in the propor-tion of alien species in close-to-nature managed forests and unmanaged forests are negligibl

Neophyten in Buchen- und Fichtenwäldern des Sollings

405 Neophyten in Buchen- und Fichtenwäldern des Sollings* Wolfgang Schmidt, Steffi Heinrichs, Martin Weckesser, Luise Ebrecht und Bernadett Lambertz Abstract: Non-native plant species in beech and Norway spruce forests of the Solling Hills The proportion of alien plant species in the ground vegetation of beech forests and Norway spruce stands on acidic soils was investigated by comparing vegetation relevés in the Solling Hills (Lower Saxony) obtained from different research projects during four decades. In general, the proportion of non-indigenous plant species is rather low. In species-poor closed beech stands 4.4 % (on average 1.3 %) of the maximum species number and 7.3 % (on average 1.9 %) of the maximum coverage of the sparsely covered herbaceous layer belong to alien plant species. In the Norway spruce stands with a more species-rich and more densely covered herbaceous layer, the proportion of alien species is 2.8 % (on average 1.4 %, species number) and 4.7 % (on average 1.7 %, coverage) at maximum, respectively. In 1966-1968, no alien plant species were recorded in managed beech and Norway spruce forests. In contrast, vegetation relevés recorded 30 years later on the same site showed an increase in the number of alien species up to 1.3 % of the mean number of species. The mean cover of non-native species increased to 0.2 % (beech) and 4.7 % (Norway spruce) of the total herbaceous layer coverage, respectively. Non-indigenous plant species are still lacking completely in the unmanaged beech forest nature reserve. Silvicultural treatments like group selection felling in beech stands or girth-limit felling and clear-cutting in Norway spruce stands were not followed by a significant increase of alien species according to the disturbance gradient. By the creation and use of skid trails in forests there was no shortterm increase of non-native species. Only on heavily or repeatedly disturbed parts of compacted forest roads and skid trails, such as wheel tracks or mid-line in Norway spruce stands did aliens increase significantly. The most important non-native herbs of beech and Norway spruce stands in the Solling Hills are Impatiens parviflora and Epilobium ciliatum. Until now, E. ciliatum was missing in the beech forests mainly due to the low light availability. Rare occurrences of spontaneous tree regeneration of introduced Pseudotsuga menziesii, Larix decidua and Quercus rubra result from near-by forest plantations and indicate that the most important impact on vegetation is coming from the plantation of exotic tree species rather than the spontaneous establishment of herbaceous neophytes. Other alien woody species as well as adventative ornamental plants which are fully established in the flora of the Solling Hills today, are presently not found in the herbaceous layer of the forests. Most of these species can be found in open landscapes or urban areas with gardens and parks. Accordingly the whole Solling landscape including the open and ruderal outskirts has a higher proportion of non-native plant species than the nearly completely forested central part of the research area (11.1 % versus 7.6 % of the flora)

Aspect construal in Mandarin: a usage-based constructionist perspective on LE

Despite extensive research efforts to explain the Mandarin Chinese particle le, confusion persists in the absence of a unitary theory and sufficient empirical evidence. This study provides a unitary account of le by adopting a usage-based constructionist approach, one that liberates grammatical aspect from, and is able to accommodate, lexical aspect. We argue that le participates in two distinct family resemblance constructions of aspect construal associated with two distinct sentential positions. The clause-internal le construction construes the closing or final boundary of an event and the clause-final le construction construes the opening or initial boundary of an event. Corpus analysis showed that the two aspect constructions have distinct patterns in natural language uses that are consistent with the proposed construals. Results from elicited response data showed that native speakers paid attention to construction-level formal and semantic cues in making family resemblance judgments about tokens of the two constructions. This study has both theoretical and methodological implications for crosslinguistic research on grammatical aspect in relation to lexical aspect and for usage-based constructionist approaches to grammatical categories beyond aspect.</p

Geo-Biological Investigations on Azooxanthellate Cold-Water Coral Reefs on the Carbonate Mounds Along the Celtic Continental Slope

Northeast Atlantic 2004 Cruise No. 61, Leg 1 April 19 to May 4, 2004, Lisbon – Cor

Seasonal drivers of understorey temperature buffering in temperate deciduous forests across Europe.

Aim:Forest understorey microclimates are often buffered against extreme heat or cold, with important implications for the organisms living in these environments. We quantified seasonal effects of understorey microclimate predictors describing canopy structure, canopy composition and topography (i.e., local factors) and the forest patch size and distance to the coast (i.e., landscape factors). Location:Temperate forests in Europe. Time period:2017-2018. Major taxa studied:Woody plants. Methods:We combined data from a microclimate sensor network with weather-station records to calculate the difference, or offset, between temperatures measured inside and outside forests. We used regression analysis to study the effects of local and landscape factors on the seasonal offset of minimum, mean and maximum temperatures. Results:The maximum temperature during the summer was on average cooler by 2.1 °C inside than outside forests, and the minimum temperatures during the winter and spring were 0.4 and 0.9 °C warmer. The local canopy cover was a strong nonlinear driver of the maximum temperature offset during summer, and we found increased cooling beneath tree species that cast the deepest shade. Seasonal offsets of minimum temperature were mainly regulated by landscape and topographic features, such as the distance to the coast and topographic position. Main conclusions:Forest organisms experience less severe temperature extremes than suggested by currently available macroclimate data; therefore, climate-species relationships and the responses of species to anthropogenic global warming cannot be modelled accurately in forests using macroclimate data alone. Changes in canopy cover and composition will strongly modulate the warming of maximum temperatures in forest understories, with important implications for understanding the responses of forest biodiversity and functioning to the combined threats of land-use change and climate change. Our predictive models are generally applicable across lowland temperate deciduous forests, providing ecologically important microclimate data for forest understories

3rd Helmholtz Open Science Forum „Helmholtz in the German National Research Data Infrastructure (NFDI)“

To promote dialogue on the National Research Data Infrastructure (NFDI) in the Helmholtz Association, the Helmholtz Open Science Office hosted two digital Forums in May and December 2021. The office has organized a third Forum on the topic on June 22, 2023. The objective of this event was to offer insights into the NFDI activities within the Helmholtz Association, presented from the internal perspectives of the Centers. Multiple Helmholtz Centers shared their experiences, fostering an interactive environment for questions and discussions. Furthermore, there were contributions highlighting the Base4NFDI basic service consortium